Hepatitis delta, also known as hepatitis D, is a liver infection caused by the hepatitis delta virus (HDV) that results in the most severe form of human viral hepatitis for which there is no approved therapy.

HDV is a single-stranded, circular RNA virus that requires the envelope protein (HBsAg) of the hepatitis B virus (HBV) for its own assembly. As a result, hepatitis delta virus (HDV) infection occurs only as a co-infection in individuals infected with HBV. However, HDV/HBV co-infections lead to more serious liver disease than HBV infection alone. HDV is associated with faster progression to liver fibrosis (progressing to cirrhosis in about 80% of individuals in 5-10 years), increased risk of liver cancer, and early decompensated cirrhosis and liver failure.
HDV is the most severe form of viral hepatitis with no approved treatment.
Approved nucleos(t)ide treatments for HBV only suppress HBV DNA, do not appreciably impact HBsAg and have no impact on HDV. Investigational agents in development for HBV target multiple new mechanisms. Aspirations are high, but a functional cure for HBV has not been achieved nor is one anticipated in the forseeable future. Without clearance of HBsAg, anti-HBV investigational treatments are not expected to impact the deadly course of HDV infection anytime soon.

Hesaam Esfandyarpour holds what looks like a mini-cooler up to the computer screen in his California office.

Esfandyarpour is in his late-30s, with crows feet creeping up against a youthful face. He wears a gray polo and the device in his hand — with its hard plastic-looking shell, blue-and-white pattern, and a white plastic paddle resembling a handle jutting out the front — might contain diced strawberries and peanut-butter sandwiches to meet mom and the kids at a SoCal park. Instead, Esfandyarpour tells me it’s going to change medicine and biopharma research.

Almost two years after leaving GSK to launch Brii Bio with a whopping $260 million in funding, Zhi Hong is seeing the trans-Pacific infectious disease specialist he set out to build take shape.

“Our pipeline is coming together,” he told Endpoints News, with 12 partnered assets plus some internal programs.

As its latest partner, AN2 Therapeutics, comes into the limelight for the first time with a $12 million seed round, so is Brii’s plans in the antibiotics space. Brii has obtained China rights to AN2’s antibacterial targeting mycobacterium tuberculosis for multi-drug resistant TB, which it says is in the clinical stage.

Nearly a century passed between the first proto-immunotherapy attempts in cancer — crude and obscure but nonetheless with some scientific basis — and Jim Allison’s first T cell paper. Thirty-plus years flipped between the discovery of CTLA-4 as an off-switch and the approval of Yervoy. Twenty-two rolled between PD-1’s isolation and Opdiva and Keytruda. 

Longwood co-founder Lea Hachigian is betting she can hasten that. It’s a bet on newly established single-cell genomic analysis tech and the ability to crunch endless troves of data at a rate few others can, and investors including Leaps by Bayer and Novartis Venture Fund just put $39 million behind it. They call it Immunitas.